docs: def import_price(self, price: PriceModel):
          """ Import individual price """
          # Handle yahoo-style symbols with extension.
          symbol = price.symbol
          if "." in symbol:
              symbol = price.symbol.split(".")[0]
          stock = SecuritiesAggregate(self.book).get_by_symbol(symbol)
          # get_aggregate_for_symbol
  
          if stock is None:
              logging.warning("security %s not found in book.", price.symbol)
              return False
  
          # check if there is already a price for the date
          existing_prices = stock.prices.filter(Price.date == price.datetime.date()).all()
          if not existing_prices:
              # Create new price for the commodity (symbol).
              self.__create_price_for(stock, price)
          else:
              logging.warning("price already exists for %s on %s",
                              stock.mnemonic, price.datetime.strftime("%Y-%m-%d"))
  
              existing_price = existing_prices[0]
              # update price
              existing_price.value = price.value
  
          return True